National Forensic Doctor-Chapter 1129 - 1060: A Bit of Scale

Jiang Yuan took Sun Jianyu’s profile in hand, meticulously reviewed it multiple times, and then had his hand and foot prints reproduced for comparison against the strangulation marks on the deceased’s body.

Sun Jianyu was less than 170 cm tall and weighed just over 40 kg, with a slim waist, thin legs, and narrow arms—a pure skinny figure. The victim, Sun Xiuwen, weighed about the same as Sun Jianyu. Despite being female and slightly weaker in terms of physical strength, it would be relatively difficult for Sun Jianyu to smother her to death on his own.

It wasn’t surprising that there were strangulation marks on Sun Xiuwen’s neck; presumably, Sun Jianyu or Liu Mingxue had assisted in the act. However, the victim’s hyoid bone was not fractured, which also indicated insufficient force in the strangulation.

Certainly, analyzing merely from the perspective of insufficient strength, Sun Jianyu’s girlfriend, Liu Mingxue—who was also Sun Xiuwen’s close friend—would be even less capable. By conventional reasoning, for Liu Mingxue, a young woman, to actively resort to a violent method such as smothering to kill Sun Xiuwen, the likelihood seemed quite low.

"From what we know so far, the two of them likely conspired, with Sun Jianyu taking the lead and Liu Mingxue assisting, jointly killing Sun Xiuwen," Jiang Yuan stated at the crime scene after briefly perusing his PAD, delivering a conclusion that wasn’t particularly surprising.

One of the most critical tasks for a forensic doctor is discerning the actual perpetrator in collaborative murder cases. An example would be a group of teenagers engaging in mutual assault, resulting in a death; in such instances, the one primarily responsible is not necessarily the person who strikes the most blows, but rather the individual who executes the fatal action.

Suppose the victim’s occiput was hit by a bottle, the heart suddenly stopped, and the thigh was punctured... The forensic doctor must determine the exact cause of death—whether it was the bottle, the thigh wound, or... in the case of cardiac arrest, it might result in collective liability and shared punishment.

Jiang Yuan identified Sun Jianyu and Liu Mingxue as co-perpetrators, and once submitted for trial, the verdict would very likely not differentiate between a primary and secondary offender.

On the other end of the phone, Meng Chengbiao listened and immediately responded, "I agree, Sun Jianyu must have been involved, and Liu Mingxue can’t escape either. Both of them are minors with immature minds. During interrogation, we’ll get results; I’m confident of that."

"Alright, I’ll leave this to you," Jiang Yuan confirmed the perpetrators, then thoroughly inspected the group’s secret hideout one more time. Afterward, he took Sun Jianyu’s motorcycle and headed back to Changyang City.

The tread marks at the secondary scene couldn’t be used for identification, but they were enough for elimination purposes. In this case, the means of transport had to be considered. Even if they couldn’t confirm the exact motorcycle used, they needed to demonstrate that Sun Jianyu had access to a similar type at the very least.

By the time Jiang Yuan returned to the Changyang City Bureau, Wang Chuanxing and others had nearly finished preparing the case files.

The case itself was indeed challenging, but the difficulty lay mainly in the circumstances; the heavy rains that night had washed away much evidence, including the footprints of Sun Jianyu climbing over walls, rendering them impossible to prove. Fresh tracks disintegrated under rainfall, while older ones remained.

Furthermore, as the perpetrators were minors, their behavioral patterns were exceedingly unpredictable—including the motives for killing and the methods of concealing the crime, which were distinctly immature.

Had it been an adult offender, not to mention whether they’d kill someone over something like cleaning and tidying a room, the post-murder handling wouldn’t have been so amateurish. They wouldn’t refrain from discarding a pillow due to fear of relatives noticing, compulsively washing and scrubbing it instead. Nor would they hurriedly abandon the body by the roadside, leaving such conspicuous tire tracks from a motorcycle.

And yet, to accuse the two of lacking intelligence wouldn’t be entirely fair; they not only discarded the body but also stripped off the victim’s clothing, staging it to look like a sexual assault.

Despite such nuances, Jiang Yuan’s focus on these details had already diminished significantly.

For Sun Jianyu and Liu Mingxue, their capacity to resist interrogation was weak. Given the existing evidence, it was sufficient to make them recount the details over and over dozens of times.

Yu Wenshu and his colleagues were particularly satisfied. Upon meeting Jiang Yuan, they kept saying, "Who’d have thought it was two minors behind this case? Our Changyang City cases just don’t seem deranged enough..."

"It’s plenty deranged already," Shen Yaowei, who had accompanied the entire process without contributing much, remarked. He was thoroughly familiar with the case and continued, "Two minors, falling out over a trivial matter, with the girlfriend and boyfriend teaming up to kill the victim. They even went on to discard the body. If this case had gone unsolved, in another ten years who knows how many more victims might have fallen prey."

Yu Wenshu nodded, "Not entirely deranged."

"We owe it to Captain Jiang; our special task force had been unable to advance the case," Cao Chujun said with some emotion. As an elder nearing retirement as a team leader, he no longer attached much importance to things like face. As his tenure drew to a close, he increasingly valued cracking major cases, as a way to honor his forty years in law enforcement.

Jiang Yuan smiled modestly and deflected the praise. Although he personally assessed the case’s difficulty as relatively low, he refrained from stating so in front of the former task force leader Cao Chujun.

Cao Chujun, however, saw through it. Old detectives possess a kind of insight into human behavior, even if they aren’t always able to solve the case.

Feeling a spark of enthusiasm, Cao Chujun quickly chipped in before Yu Wenshu could speak, striking while the iron was hot: "Captain Jiang, there are plenty of deranged cases, particularly old unresolved ones. Some case files are too old, making them difficult to investigate..."

This was akin to laying bait outright.

Cao Chujun gazed at Jiang Yuan warmly.

Jiang Yuan smirked, glanced at Yu Wenshu, and then replied, "We don’t necessarily have to pursue deranged cases; solving regular murder cases delivers a strong sense of accomplishment as well."

Yu Wenshu interjected at this point, "You usually bring along over 30 people; handling average cases might be inefficient for your team, right?"

Jiang Yuan froze for a moment—he hadn’t considered that.

Cao Chujun chuckled slyly, eyeing Yu Wenshu while his tone shifted to a more formal note: "Speaking of deranged cases, the 303 Special Case, in my opinion, certainly qualifies."

"The 303 Special Case..." Yu Wenshu quickly delved into recollection: "The victims were 31-year-old female Zhao Qian, 28-year-old male Qin Jijian, and 35-year-old male Gu Daxu... The three were killed at Zhao Qian’s home while engaging in a ménage à trois?"

"Yes, that’s the case. You even remember the victims’ names—remarkable..." Cao Chujun complimented with the overly traditional and flattering tone pervasive in the Changyang City Criminal Police Detachment, eliciting laughter from Yu Wenshu.

"The 303 Special Case is indeed rather deranged. The perpetrator was skilled, ruthless, and the case has remained unsolved for seven to eight years—it would benefit from a fresh assessment," Yu Wenshu remarked, casting a glance toward Jiang Yuan. "I assure you, the level of this case far surpasses the previous one in terms of intensity."

"There’s no necessity to pursue cases for their deranged nature or extremes," Jiang Yuan sighed.

"This case is quite extraordinary," Cao Chujun steered the conversation, stating, "The perpetrator broke into the home through the balcony security bars, which he bent open by hand. Upon entry, he killed three people in succession, cleaned the scene, and left swiftly with remarkable efficiency and skill. No blood footprints or traces of the perpetrator’s DNA were found at the scene."

"Were all three people single?"

"No, they were married," Yu Wenshu preemptively answered Jiang Yuan’s probable question, adding, "The spouses of all three victims were investigated; they had alibis. Moreover, the victims had multiple sexual partners, some of whom were discreet. The case has remained difficult to pin down a suspect."